Add flag for enabling WebRTC AEC debug recordings.

content/renderer/media/rtc_media_constraints.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 #include "content/renderer/media/rtc_media_constraints.h"
 
 #include "base/logging.h"
-
+#include "base/string_util.h"
 #include "content/common/media/media_stream_options.h"
 #include "third_party/WebKit/Source/Platform/chromium/public/WebMediaConstraints.h"
 #include "third_party/WebKit/Source/Platform/chromium/public/WebCString.h"
 #include "third_party/WebKit/Source/Platform/chromium/public/WebString.h"
 
 namespace content {
 namespace {
 
 void GetNativeMediaConstraints(
     const WebKit::WebVector<WebKit::WebMediaConstraint>& constraints,
     webrtc::MediaConstraintsInterface::Constraints* native_constraints) {
   DCHECK(native_constraints);
   for (size_t i = 0; i < constraints.size(); ++i) {
     webrtc::MediaConstraintsInterface::Constraint new_constraint;
     new_constraint.key = constraints[i].m_name.utf8();
     new_constraint.value = constraints[i].m_value.utf8();
 
     // Ignore Chrome specific Tab capture constraints.
     if (new_constraint.key == kMediaStreamSource ||
         new_constraint.key == kMediaStreamSourceId)
       continue;
+
+    // Ignore internal constraints set by JS.
+    // TODO(jiayl): replace the hard coded string with
+    // webrtc::MediaConstraintsInterface::kInternalConstraintPrefix when
+    // the Libjingle change is rolled.
+    if (StartsWithASCII(new_constraint.key, "internal", true))
+      continue;
+
     DVLOG(3) << "MediaStreamConstraints:" << new_constraint.key
              << " : " <<  new_constraint.value;
     native_constraints->push_back(new_constraint);
   }
 }
 
 }  // namespace
 
 RTCMediaConstraints::RTCMediaConstraints(
       const WebKit::WebMediaConstraints& constraints) {
@@ skipping 12 matching lines @@
 const webrtc::MediaConstraintsInterface::Constraints&
 RTCMediaConstraints::GetMandatory() const  {
   return mandatory_;
 }
 
 const webrtc::MediaConstraintsInterface::Constraints&
 RTCMediaConstraints::GetOptional() const {
   return optional_;
 }
 
+void RTCMediaConstraints::AddOptional(const std::string& key,
+                                      const std::string& value) {
+  optional_.push_back(Constraint(key, value));
+}
+
 }  // namespace content